Method of and apparatus for forming folded paper stacks



Dec. 22, 1959 L. T. HAND ET AL METHOD OF AND APPARATUS FOR FORMING FOLDED PAPER STACKS Filed Nov. 27, 1956 g &

3 Sheets-Sheet 1 Les/A9 7T H000 Jas/ah N Macy Afforneys Dec. 22, 1959 T. HAND ETAL METHOD OF AND APPARATUS FOR FORMING FOLDED PAPER STAGKS 3 Sheets-Sheet 2 Filed NOV. 27, 1956 Alfom eys Dec. 22, 1959 L. T. HAND ETAL 2,918,277

METHOD OF AND APPARATUS FOR FORMING FOLDED PAPER STACKS Filed Nov. 27, 1956 3 Sheets-Sheet 3 Mme/Wars F/ G. Les/[e Z'Hano Jas/ah /V. Macy Af/omeys METHOD OF AND APPARATUS FOR FORMING FOLDED PAPER STACKS Leslie T. Hand, Greenwich, Conn., and Josiah N. Macy, Washington, D.C.

Application November 27, 1956, Serial No. 624,659

Claims. (Cl. 270-73) The present invention relates generally to the manufacture of zig-zag folded paper tapes and, more particularly, to a method and apparatus for manufacturing stacks of zig-zag folded paper in tape widths.

The use of recording and punch-type machines using relatively narrow paper tapes is steadily increasing, and it has been found desirable in such machines for the purposes of tape storage and tape replacement to use tape in the form of zig-Zag folded stacks in tape width of about an inch or so and in stacks of a foot or more in height which contain several hundred feet or more of tape in a compact space. In manufacturing these zig-Zag folded tapes for use in present recording instruments, it is necessary that the lengths of the individual folds be kept uniform so that the completed stacks are rectangular in shape and so that they have straight sides. Machinery has been developed to fold such tapes to the degree of tolerance required by folding relatively wide webs of paper and by thereafter cutting or separating the folded webs into individual stacks of tape width. Such machines are disclosed in United States Patents Nos. 1,985,- 676 and 2,531,213. Although the machines disclosed in these patents provide zig-zag folded stacks of paper having satisfactory tolerances and straight sides, considerable difliculty has been encountered in dividing the relatively wide Zig-zag folded stacks into narrow stacks of tape width for use in the recording machines. Attempts to fold the paper in tape widths originally have proven slow and costly.

An attempt has been made to expedite the division of the Wide folded stacks into narrow stacks by partially slitting the web prior to the folding action so that the partial slits will assist in the division of the stack. Even where these partial slits have been provided, however, the division of the stack still comprises a difficult operation as the tightly folded layers of paper tend to cling to one another after they have been compacted into relatively tight blocks. The apparatus and method of the present invention forms the zigzag stacks from a wide web to retain the advantages of the wide folding drums and separates the zigzag folded stack automatically and continuously into tape width Zig-zag folded stacks.

Accordingly, an object of the present invention is to provide an improved method and apparatus for manufacturing narrow stacks of zig-zag folded paper.

Another object of the present invention is to provide an efiicient and relatively simple method and means for dividing a relatively wide stack of zig-Zag folded paper into a plurality of narrow stacks.

Another object of the present invention is to provide a method and means for forming narrow zig-zag folded stacks which method and means are adapted for continuous operation on a high-speed folding machine.

Another object of the present invention is to provide a separator for a zig-Zag folded stack which is adaptable for use with presently known types of folding machines.

I United States Patent 0 Other and further objects of the invention will be obvious upon an understanding of the illustrative embodiment about to be described, or will be indicated in the appended claims, and various advantages not referred to herein will occur to one skilled in the art upon employment of the invention in practice.

A preferred embodiment of the invention has been chosen for purposes of illustration and description and is shown in the accompanying drawings, forming a part of the specification, wherein:

Fig. 1 is a diagrammatic representation of a mechanism for performing the method of the present invention;

Fig. 2 is an enlarged front elevational view of the stack separator;

Fig. 3 is a sectional view of the drive crank of the separator motor taken along line 33 of Fig. 2;

Fig. 4 is a sectional view of the partially slit paper web taken along line 44 of Fig. 1;

Fig. 5 is a sectional view of the mechanism of Fig. 1 taken along line 5-5 of Fig. 1 showing the action of the separator blades on the folded web;

Fig. 6 is a sectional view of the separator of Fig. 2 taken along lines 6-6 of Fig. 2;

Fig. 7 is an enlarged detailed view of another embodiment of the drive mechanism for a separator.

Fig. 8 is an enlarged detailed view in section of the web slitting means;

Fig. 9 is a perspective view of a tape width stack of folded paper as formed by the method and means of the present invention;

Fig. 10 is an enlarged fragmentary view partially in section of another embodiment of a separator;

Fig. 11 is a sectional view taken along line 11-11 of Fig. 10; and

Fig. 12 is a detailed perspective view of the separator blade mounting for the separator blades of Fig. 10.

The method and apparatus for forming the zig-zag folded stacks will first be described generally with particular reference to Fig. l. The stack making machine 1 having its components mounted upon a suitable frame 2 folds a relatively wide paper web 3 which is supplied from a roller 4. Web 3 is first carried on suitable rollers 6 and 6a past a slitter indicated generally at 5 which forms longitudinal partial slits 7 (Fig. 4) which are separated at intervals by an unslit or connecting portion 8. After the web 3 passes the slitter 5, it is conveyed on rollers 6 to the upper and central portion of the frame 2, at which point it is fed into the folding mechanism indicated generally at 9.

Folding mechanism 9 comprises two adjacent cylindrical folding drums 10 and 11 having cooperating fold ing jaws 12 and folding blades 13 spaced on their periphery. As the folding drums 10 and 11 rotate, successive pairs of folding jaws 12 and folding blades 13 grip the web 3 between them forming lateral creases in web 3 so that oppositely directed and spaced folds are formed in the web resulting in the formation of a zig-zag folded stack 15 of folded paper beneath the drums 10 and 11. A suitable folding mechanism 9 is described in detail in United States Patent No. 2,531,213. Other suitable types of zig-zag folder mechanisms may be used.

Since the folding jaws 12 and the folding blades 13 are alternately positioned on the folding drums 10 and 11 so that each jaw on one drum cooperates with a corresponding folder blade 13 on the other drum, it will be seen that the jaws 12 carry the folds of the web in opposite directions at the lower portion of the drumsto form a stack 15 centrally located beneath the drums 10 and 11. The lower portion of the folded stack 15 is sup ported by a conveyor 16 which moves the lower portion of the stack beneath the folding drum 11 towards the right-hand side of stack making machine 1. The speed of the conveyor 16 is adjusted so that the folded web rests on conveyor 16 in relatively loose folds 14 which tend to stand partially upright with respect to conveyor 16.

As the loose folds 14 are moved by the conveyor 16 to the right-hand end of the stack making machine 1, they are moved through the separator 17, which, as will be more fully described below, separates the folded and partially slit web 3 into a plurality of individual tape width stacks. The divided stacks 18 are carried by a suitable conveyor 19 to a stacking shelf 20 which receives the divided stacks 18 and orients them in generally horizontal position so that the stacks 18, being moved from the right-hand end of conveyor 19, form themselves into a relatively compact and vertical stack 25. In the preferred embodiment illustrated in Fig. 1, the stacking shelf 20 is slidably supported on vertical rods 21 by bearings 22. An endless chain 24 is connected at one point to the stacking shelf 20 so that as it rotates, it

lowers the shelf 20 to accommodate for the increasing depth of stack 25 being formed on the shelf 20. Endless chain 24 is operated and connected to the main drive motor 26 by a suitable coupling. The main drive motor 26 is also connected to folding mechanism 9, conveyors 16 and 19, and drive roller 6a by suitable coupling members to drive them at suitably coordinated speeds.

As described above, the relatively broad web 3 is divid ed into tape width stacks by the action of separator 17 on the longitudinal slits 7. Slits 7 are formed by the slitter 5, which is shown in greater detail in Fig. 8. Slitter comprises a plurality of circular knives 30 each rotatably mounted on a shaft 32, which is fixed in sup port member 33. Web 3, passing between the rotating knives 30 and roller 6a, is slit by the circular cutting edge of knife 30, with the exception of the portion bridged by the nick 31 formed in the knife 30. Thus, as the web 3 rolls upwardly on the roller 6a, the slits 7, as seen in Fig. 4, are formed having uncut or connecting portions 8 therebetween. Each support member 33 is slidably mounted on the surface of a support 34. An elongated aperture 36 is provided in support member 33 to accommodate screw 37 which is threadedly connected to threaded o'rifice 38 in support member 34. Spring 39 bridges the top of aperture 36 to adjustably hold the support member 33 in place under spring tension. Fine adjustments of the support member 33 toward roller 6a are provided by bolt 41 which is rotatably mounted in orifice 42 of the support member 34 and which is threadedly connected at 40 to the support member 33. A spring 44 is mounted between member 33 and member 34 to urge member 33 towards the end of the bolt 41 and to hold bolt 41 in position against member 34.

Adjustment of each of the knife support members 34 laterally of the web 3 is provided by having it slidably mounted upon an elongated support member 35 which is seen in section in Fig. 5. Cooperating lips 46 on members 34 and 47 on member 35 cooperate to retain the forward edge of member 34 and a set screw 48 adjustably engages the rear surface of member 35 to lock the member 34 in position. The lateral support member 35 is attached to frame of the machine 1.

After the web 3 has been partially slit by the slit 7 and folded into zig-zag stacks by the folding mechanism 9, as discussed above, loose folds 14 of the web are carried to the separator means 17 by the horizontal conveyor 16. As seen in Figs. 1 and 5, stack separator 17 is mounted between the end of the conveyor 16 and the front of conveyor 19 so that the folds 14 are moved through it by the cooperative motion of conveyors 16 and 19. The separator means 17, which is shown in detail in Figs. 2, 3, and 6, has a plurality of vertical separator bars 54 each one of which is positioned in a slit 7 of the web 3. The separator bars 54 complete the separation of the web 3 into separate folded stacks, as seen in Fig. 5, by severing or tearing the connecting portions 8 in web 3 between the slits 7 as the folds 14 of 4 the folded web are moved past the separator 17 by the conveyors 16 and 19.

A preferred embodiment of the separator means 17 is illustrated in Figs. 2, 3, and 6. The separator means 17 comprises a plurality of vertical separator bars 54 adjustably mounted on a horizontal separator frame 55. Although a certain amount of separating action is ob tained by using stationary separator bars 54, it has been found that the application of a vibratory motion to the separator means 17 provides for a significant increase in the operating efficiency of the separating means and allows it to be run at much higher speeds and to handle heavier grades of folded paper without any jamming or bunching on the conveyors.

A preferred embodiment of a vibrating means is illustrated in Fig. 2. The separator frame 55 comprises top and bottom bars 56 and 57, respectively, suitable fastened to end pieces 58. The entire separator frame 55 is slidably mounted on upper and lower mounting rods 59 and 60, respectively, by means of bushings 61 fitted into the end pieces 58. The mounting rods 59 and 69 are attached to the frame 10 of the stack making machine 1 by suitable mounting brackets 62. Bushings 61 may be any suitable type bushing which allows the frame 55 to slide easily along the rods 59 and 60. Ball bushings have been found to provide a practical frictionless support for the separator frame 55 on rods 59 and 60. The separator bars 54 are adjustably mounted on the top bar Y 56 of the separator frame 55 to allow for the adjustment of their spacing for varying widths of folded stacks. A convenient method of mounting the adjustable separator bars 54 is illustrated in Fig. 2. The separator bars 54 are provided with a right-angled foot 66 to which a threaded lug 67 is fastened in a suitable manner, such as by welding. Lugs 67 are inserted into an elongated slot 69 which runs along the top bar 56 of the frame 55. Bolts 68 engage the threaded lugs 67 to hold separator blades 54 in the particular spacing pattern desired. A

' widened portion 69a is provided at the top of slot 69 to allow the feet 66 to be flush with the top of bar 56.

A vibrator means 70 is provided to impart a horizontal reciprocating motion tothe separator bars 54 by moving the separator frame transversely on the rods 59 and 60. Vibrator 70 comprises a drive motor 71 having a crank 72 mounted thereon and operatively connected to the separator frame 55 by a connector rod 73. Connector rod 73 is attached to the separator frame 55 by a suitable pin 81 and is pivotally attached to the crank 72 by pin 76. In order to provide for an adjustment of the amount of horizontal travel imparted to the separator bars 54, pin 76 is slidably mounted on crank 72 in a T-slot 75 as seen in Fig. 3. The radial position of the pin 76 on the circular crank 72 is adjusted by sliding pin 76 to its desired position in slot 75 and by locking it in this position by a suitable set screw 79. Drive motor 71 preferably has an adjustable speed control 71a so that the vibration rate of the bars 54 may be controlled as desired to provide for the most efiicient separating action. 1

Although the use of an essentially transverse vibratory motion as described in connection with Fig. 2 has proven to be effective with certain materials, it has been found that a vibratory component of motion longitudinal to the folded web helps in the separating action. In Fig. 7, another embodiment of the separator frame and the vibrator therefor is illustrated in which both lateral and longitudinal vibratory movement is provided for the separator bars 54'by mounting the frame 55 on a single mounting rod 59 and by imparting a generally circular movement to the lower rod 57 of the frame 55' by drive means 70. Drive means 70' comprises a drive motor 71' mounted in a generally vertical position having a crank 72 operatively connected to the frame 55' by pin 73. Pin 73' is rotatably connected to the bottom bar 57 in a suitable bushing 82 which loosely engages pin 73 to allow for a rocking motion of frame 55'. Pin 73' is mounted eccentrically on the crank 72 to impart a generally circular motion to the separator bars '54 through frame 55' and bushing 82.

Another embodiment of the separator is illustrated in Figs. 1042. This separator 90 has a separator frame 91 mounted for reciprocal movement laterally of the folding machine 1 on mounting rods 92. Separator frame 91 is slidably connected to the rods 92 by suitable bushings 94, and the mounting bars 92 are connected to the frame of the stack making machine 1 by suitable mounting brackets 95. On the top bar 96 of the separator frame 91 a plurality of separator bars 97 .are pivotally mounted having a lower bearing portion 98 which is pivotally attached in suitable bearings 99 in top bar 96.

In order to provide an oscillating motion which turns each of the separator bars 97 about its vertical axis, a pinion 100 is attached to a shaftlike extension 101 on the bottom of bearing portion 98. Each of the pinions 100 engages cooperating teeth 102 in a horizontal rack 104 which is fixedlymounted adjacent to the separator frame 91 on the mounting brackets 95. A drive means 105, comprising a drive motor 106 having a connected crank member 107 and connector rod 108 similar to that described above in connection with vibrator means 70, imparts a reciprocating motion to the separator frame 91. As the frame 91 is reciprocated axially of the mounting rods 92, the pinions 100 are moved back and forth and along the rack 104 so that an oscillatory type of rotary motion is imparted to each of the pinions 100 and to the connected separator bars 97. The type of oscillatory motion imparted to the separator bars 97 may be set by positioning the separator bars 97 on the surface of the bearing portion 98. To provide for this adjustment, the bearing portion 98 is formed in an upper portion 98a and a lower portion 9817. A slot 109 is formed in upper portion 98a to accommodate the blade fastening screw 98c. Suitable screws 98d fasten portions 98a and 98b together. The angle of rotation of each of the separator bars 97 may be adjusted by suitable adjustment of the connecting pin 110 for crank 108 in T-slot 111 of the crank 107. With the separator 90, the additional oscillatory movement of the separator bars 97 in conjunction with the lateral motion of the separator bars provides a compound separating thrust for each of the separator bars 97, which facilitates the separating action of the separator bars 97 in the slit 7 of the folded web.

In Figs. 10-12 another embodiment of the separator blade bar is shown in which each separator bar has a generally oval horizontal cross section (Fig. 11) which tapers from the relatively large cross section at the base of the bar to a relatively thin cross section at the upper portion of the bars as seen in Figs. 10-12.

The operation of the stack making method and apparatus which has been described in detail above may be summarized as follows. The paper web 3 is supplied to the machine 1 in suitable rolls 4 and is fed from roll 4 over suitable rollers 6 and 6a through the slitter 5 and thence to the folding mechanism 9. As the web is drawn past the slitter 5 by roller 6a, the rotating circular nicked knives 30 form a plurality of longitudinal slits 7 in the web 3 separated by unslit or connecting portions 8. Thereafter the paper is fed on rollers 6 to folding mechanism 9. At the folding mechanism 9 cooperating and alternately positioned folding jaws 12 and folding blades 13 grip and fold the web 3 with lateral folds. Each of the folds is retained in the folding jaw 12 until the folding drum has carried it to a point above the conveyor 16 positioned between the folding drums. Since the alternate folding jaws 12 are turning in opposite directions on folding drums 10 and 11, respectively, adjacent folds are released at spaced points beneath the drums 10 and 11 so that the zig-Zag folded web is deposited in loose folds 14 on the conveyor 16. (Jonveyor 16 moves the loose folds 14 against the separator means 17 as seen in Fig. 5. Each of the separator bars 54 of the separator means 17 is positioned in one of the partially formed slits 7 in the moving web 3. As the folds 14 are moved past the separator 17 by cooperating conveyors 16 and 19, the unslit or connecting portions 8 of the web are moved against the separator bars 54 of the separator 17 and are torn or separated so that the zig-zag folded web emerges from the end of conveyor 19 as a plurality of separate zig-zag folded stacks. In the preferred embodiments of the separator illustrated in Figs. 2, 3, 6, and 7, the separator 17 is vibrated by suitable drive means 70 or 70'. The vibration of the separator bars 54 expedites the above-described separating action so that the folded web is quickly and effortlessly divided into separate stacks. After the web 3 is divided into separate loosely folded stacks of conveyor 19, conveyor 19 moves the divided stacks 18 to a stacking shelf 20 which is disposed beneath the end of conveyor 19 to receive the folded web and to cause it to pile upwardly into relatively tight zig-zag folded stacks of tape width. The position of the stacking shelf 20 is continuously lowered by connected drive belt 24 to accommodate for the increasing height of the stack 25 on shelf 20. The zig-zag folded stacks 25 may be removed from shelf 20 when they have reached the desired height, and shelf 20 may be detached from drive belt 24 and raised to a suitable position to commence the formation of another set of stacks.

The embodiment of the separator shown at in Figs. 10-12 operates in a manner generally similar to the above-described operation of the separator 17. An additional oscillatory motion, however, is provided by the partial rotation of the individual separator bars 97 about their vertical axes. The amount of the lateral reciprocal motion of the separator bars 97 is adjustable by setting the position of the pivot 1.10 on the drive motor crank 107 at the radial position desired. The pivotal path of the separator bars 97 may also be adjusted by positioning each bar 97 in the adjustment slot 109 on the bearing portion 98. Thus, if the separator bar 97 is positioned centrally of the bearing portion 98, a rotary motion about the vertical axis will result. If the separator blade is moved outwardly from the center of the bearing portion 98, as seen in Fig. 12, an arcuate path will be followed by the separator bar 97. Where it is desired to adjust the angle of rotation of the bars 97 on their bearing portions 98 independently of the motion of the separator frame 91, the pinions 100 may be changed for pinions of the necessary diameter, and the mounting of the rack 94 may be adjusted to provide a suitable meshing action with the new pinions 100.

The separator 17 is shown in the illustrated embodiment as being positioned beneath folding drum 11 between conveyors 16 and 19. It has also been found that the separator 17 may be located adjacent to the shelf 20. In this embodiment, the two conveyors: 16 and 19 are replaced by a single conveyor and the separator 17 is placed between the end of the conveyor and the shelf 20.

It will be seen that an improved apparatus and method for forming stacks of zig-zag folded paper in tape widths has been disclosed which forms a plurality of the folded stacks from a roll of relatively wide paper automatically and at relatively high speeds. The machine and apparatus take advantage of the inherent accuracy, economy, and high-speed operation of web folding mechanisms using relatively wide paper webs and at the same time produce folded stacks which are cleanly divided into suitable tape widths. The difficult and time-consuming step of cutting the zig-zag folded web after its formation into relatively wide zig-zag folded tapes is eliminated. The method and apparatus of the present invention are relatively simple and effective and may be quickly adapted to existing web folding machinery. Close tolerances in both the lengths of the tape folds and in the width of the folded tapes are maintained and the apparatus and method are easily adjusted to provide for a variety of tape widths. The'tape separating means is adaptable for use at high speed so that it may be used with tape folding apparatus at its maximum output speed.

As various changes may be made in the form, construction and arrangement of the parts herein without departing from the spirit and scope of the invention and without sacrificing any of its advantages, it is to be understood that all matter herein is to be interpreted as illustrative and not in a limiting sense.

Having thus described our invention, we claim:

1. The method of forming a plurality of relatively narrow zig-zag folded stacks of paper from a relatively wideweb of paper which comprises the steps of continuously moving said web from a supply means to a receiving means, continuously folding said moving web into zig-zag folds at a point intermediate to said supplying means and said receiving means, continuously laying said folded web on a generally horizontal conveyor with the folds adjacent to one another in a loosely folded partially upright position and moving said folds on said conveyor to said receiving means, continuously forming an interrupted longitudinal slit in said moving web prior to the folding of the web, inserting a separator bar into the interrupted slit in the folded web intermediate the ends of said conveyor, vibrating said separator bar as the folds are continuously moved past said separator bar by said conveyor whereby the web is continuously separated at the slit, and thereafter stacking the folded and separated web at the receiving means.

2. The method as defined in claim 1 in which said. separator bars are vibrated laterally of the longitudinal slits in the web.

3. The method as defined in claim 1 in'which said separator bars are vibrated both laterally and longitudinal- 1y of the slits in the web.

4. The method as defined in claim 1 in which said separator bars are vibrated in a rocking motion about an axis parallel to the plane defined by the slit in the folded web.

5. A machine for forming a plurality of zig-zag folded webs from a relatively wide unfolded web of paper comprising the combination of web supply means, web receiving means, means to,move said web continuously from said supply means to said receiving means, folding means for said web intermediatesaid supply means and said receiving meansadapted to fold continuously said moving web into' zig-zag and loosely arranged folds, said web moving means including a generally horizontal conveyor having one end positioned below said folding means and adapted to receive the folded web continuously from said folding means and to carry the folds in loosely folded partially upright position to said receiving means, a web slitting means positioned intermediate said web supply means and said folding means and adapted to form continuously an interrupted slit longitudinally of said moving web, web separating means positioned on the path of said conveyor and including a separator bar positioned in the interrupted slit in the web folds on said conveyor, and vibrator means operatively connected to said separator bar to vibrate it with respect to said moving web whereby said folded moving web is separated into a plurality of folded webs.

6. The machine as claimed in claim 5 in which said separator bar comprises an elongated relatively thin plate member with a dull edge facing the interruptions in the interrupted slit of the web and mounted in the plane defined by the interrupted slit in said folded web.

7. The machine as claimed in claim 5 in which said vibrator means has a reciprocal motion directed laterally of said folded web whereby said separator bar moves between opposite edges of said interrupted slit.

8. The machine as claimed in claim 5 in which said separator bar comprises an elongated member pivotally mounted for rotary motion about its longer axis, and said vibrator means rocks said separator bar about the longer axis on the pivotal mounting.

9. The machine as claimed in claim 5 in which said vibrator means has a motion both laterally and longitudinally of said folded web whereby said separator bar moves both along said slit and between its opposite edges.

10. The machine as claimed in claim 9 in which said vibrating means has a circular motion whereby said separator bar is driven in a circular path within said slit.

Morden May 9, 1916 Sabee et a1. Sept. 4, 1956 

